1. Field of the Invention
The present invention relates to electronic systems and methods for controlling volume of audio output devices, and particularly to a system and method for controlling sound volume according to an elapsed time of operation of a manual input unit.
2. Background of the invention
Presently, there are many kinds of audio output apparatuses used for amplifying audio signals of devices such as loudhailers, TVs and MP3 (Moving Picture Experts Group, audio layer 3) players. These audio output apparatuses are known as “audio frequency amplifier apparatus,” and are used to adjust the output voltage of the device according to manual adjustment operations and corresponding adjustment commands.
A conventional audio output apparatus provides a single key for adjusting volume, and a separate muting key for muting the volume. The apparatus cannot simultaneously adjust volume and perform muting by operation of a single key. Additionally, the apparatus generally adjusts volume from a minimum amount to a maximum amount level by level. This takes much time, which often inconveniences users.
Accordingly, what is needed is a system and method for quickly and conveniently adjusting volume according to user need.